Asymmetrical urea derivatives of monoazo-dyestuffs



I tively to one another,

ASYIVIMETRICAL UREA DERIVATIVES OF MON OAZO-DYESTUFFS Hans Wilhelm Liechti, Riehen, and Raymond Gunst, Binningen, Switzerland, assignors to Ciba Limited, Basel, Switzerland, a Swiss firm No Drawing. Application April 29, 1952, Serial No. 285,058

Claims priority, application Switzerland May 25, 1951 5 Claims. (Cl. 260-175) The present invention provides new asymmetrical urea derivatives of monoazo-dyestuffs, which contain a single sulfonic acid group as, for example, in the case of the urea derivative of the formula HOsS and which correspond to the general formula in which R1 represents a benzene radical in which the groups N=N and NH are in para-position rela and R2 represents the radical of a l-hydroxy-benzene-Z-carboxylic acid bound in the 4-position to the azo linkage.

The urea derivatives of the Formula 2 can be made, by treating with phosgene two monoazo-dyestufis of the formulae HO N=NR1NH2 H O O O and HzN N=NRa in which R1 and R2 have the meanings given above, and so selecting the starting materials that the resulting asymmetrical urea derivative contains a single sulfonic acid group.

The monoazo-dyestufl s of the Formula 3 can be made i 2-carb0xylic acid-6-sulfonic acid with the amine of the formula HR1NH2 is carried out in a manner in itself known in a weakly acid medium, for example an acetic acid medium. Amines which couple with diificulty such,

0 H3O Cl 2,777,840 Patented Jan. 1-5,. 1957 for example, as aminobenzene, are advantageously coupled in the form of their so-called w-methane sulfonic acids and the w-methane sulfonic acid group i subsequently'split oft.

The monoazo-dyestuffs of the Formula 4 also used as starting materials in the present process can be made by coupling diazotized' l-amino-2-chloro-4anitro-benzene or diazotized 1-amino-2-chloro-4-acetylamino-benzene with 1-hydroxybenzene-Z-carboxylic acid or, if desired, with a substitution product thereof capable of coupling, and converting into an NH2- group the nitroor acylamino-group present in para-position to the azo linkages resulting monoazo-dyestuif.

In connection with the preparation of the monoazodyestuffs of the Formula 4 it may be mentioned that couplings with hydroxy-carboxylic acids are advantageously carried out in an alkaline medium, for example, a medium rendered alkaline with the hydroxide of an alkali metal or of an alkaline earth metal or of magnesi- OOOH The hydrolysis of dyestufis containing acylamino groups may be carried out, for example, by heating the dyestuffs in a. dilute solution of an alkali hydroxide or in a dilute mineral acid.

The linking of the amino-monoazo-dyestufis of the Formulae 3 and 4 by means of phosgene to form the asymmetrical urea derivative is advantageously conducted in an aqueous medium, and preferably with dyestuffs in the form of their alkali salts and with the addition to the reaction mixture of an acid-binding agent such, for example, as an alkali carbonate, alkali acetate or ,an alkali ortho-phosphate or alkali pyrophosphate, in order, by virtue of the butter action of these additions, to maintain the pH value Within the range of about 9.5 to 5.5 which is especially favorable for the reaction with phosgene.

The new dyestuffs of the invention, which have the above Formula 2, are suitable more especially for dyeing or printing cellulose materials such as cotton, linen, and artificial silk or staple fibers of regenerated cellulose. The dyeings obtainable on these fibrous materials with the new dyestulfs by the usual methods of direct dyeing, for example, with the addition of sodium sulfate and sodium carbonate, are distinguished by good properties of fastness and a very good capacity for being discharged.

Especially valuable dyeings, which are distinguished by very good fastness to washing and light, are obtained by treating the dyestuffs on the fiber or partially on the fiber and partially in the dyebath with an agent yielding metal. It is of advantage to use, for example, the process of U. S. Patent No. 2,148,659 in which first the dyeing and then the treatment with an agent yielding metal are carried out in one and the same bath. As agents yielding metal there come into consideration advantageously agents yielding copper, and especially those which are stable to alkaline solutions, such as complex copper tartrates.

Very valuable dyeings are obtained by using the process in which dyeings tor printsproduced with the metal free dyestutfs are aftertreated with an aqueous solution containing a basic formaldehyde condensation product with a compound which contains at least once diazotized l-amino-Z-chloro-4 nitrobenzene with 1-hythe atomic grouping droxybenzene-Z-carboxylic acid, and then reducing the nitro group) and 7.62 parts of the aminoazo-dyestuff from diazotized 4-amino-l-hydroxybenzene-Z-carboxylic 5 acid-d-sulfonic acid and 1-amino-2-methoxy-5-methylben- N zene are dissolved in 1000 parts of water in the form of the sodium salt, parts of crystalline sodium pyroor a compound such as cyanamide easily convertible phosphate are added as a buffer substance, and phosgene into a compound containing the aforesaid grouping, and is introduced into the solution at C. while stirring.

which solution also contains a water-soluble copper com- 10 When the pH value of the reaction mixture has dropped pound. Such a process is described, for example in to 5.5 the pH value is restored to 9.5 by the addition of British Patent No. 619,969. sodium hydroxide solution and further phosgene is intro- The following examples illustrate the invention, the duced until amino groups can no longer be detected. parts and percentages being by weight: The new dyestnff of the formula H00 0 CH: O1

is separated in the form of a green gelatinous precipitate Examp 1e 1 by filtration from the reaction mixture which has now 17-25 Parts of 1-amifi0-2-d1101'0-4-I1itY0benZeHe are become acid. It is precipitated from a weakly alkaline diazotized in known manner and coupled with 13.8 parts aquecus solution i the form of its sodium salt or amf 1-hydroxybenzene-l-carboxvlic acid in a Weakly a amonillm salt by the addition of sodium chloride, filtered line soluiiofl- A Solution of Paris of Sodium y oh. and dried. it is a pale brown powder, which dissolves sulfide in 50 parts of water is then run in, and the whole in water with a yellow coloration, and dyes cotton and is stirred at 6070 C. untl t e reducti n of t t fibers of regenerated cellulose yellow tints having good group is finished. 29.1 parts of the separated and dried properties of fastness and a good capacity for being disamifloazo-dyestufi, a corresponding quantiilfl of the 30 charged under alkaline and neutral conditions. filter paste of the said dyestufi, are dissolved with 35.1 By dyeing by th single bath or Z-bath after-coppering par s of -a lf '-l Y Y- process there are obtained yellow tints having very good 3'-S11lf0111C Y acld 2000 P s of water properties of wet fastness and fastness to light, and which with the addition of sufiicieut sodium carbonate to pro- 1 di harge well, duce a distinctly alkaline reaction, and the whole is E l 3 treated with phosgene at 35-40 C. in the presence of xamp 6 sodium acetate as an acid-binding agent, the sodium car- 29.1 parts of 4-amino-2-chloro-4-hydroxy-1:1'-azobonate being frequently replaced as it is consumed, until I benzene-3'-carboxylic acid prepared as described in the amino groups can no longer be detected. The completely first paragraph of Example 1 and 36.5 parts of 4-aminoprecipitated dyestufi of the formula 40 2:5-dimethyl-4'-hydroxy-1:1-azobenzene 3- carboxylic H038 CH: COOB'.

is separated by filtration and dried. It is a yellow brown acid-5-sulfonic acid' are treated with phosgene in the powder which dissolves in water with an orange coloramanner described in Example 1 until the amino groups tion and dyes cotton and regenerated cellulose handsome have disappeared. The separated and dried dyestufi of yellow tints having good properties of wet fastness and the formula net s on: 00013 H000 CH: 01 fastness to light, and a very good capacity for being is a brown powder which dissolves in water with an discharged under neutral and alkaline conditions. By orange coloration, and dyes cotton and regenerated celluafter-coppering in a single or 2-bath process there are lose handsome yellow tints having good properties of wet produced with this dyestufi somewhat more reddish tints fastness and fastness to light and a very good capacity for having y good p p of wet fastlless 311d fastlless' being discharged under neutral and alkaline conditions. t0 hght- By the single bath or 2-bath after-coppering process there Y using instead of Y Y Y' are obtained somewhat more reddish tints having very Y 1:ll'azobenzene'3"sulfonic aciddwarboxyfic acid good properties of wet fastness and fastness to light.

amino-Z-rnethoxy-4'-hydroxy-1 1-azobenzene3'-sulfonic acid-5'-carboxylic acid for producing the asymmetrical urea derivative, there is obtained a dyestufi having the r same good properties, and which produces on cotton directly and when coppered somewhat more reddish tints.

By using, instead of 4-amino-2:5dimethyl-4'-hydroxyl:1'-azobenzene- '-carboxylic acid-5-sulfonic acid, 4- amino-Z:S-dimethoxy-4-hydroxy 1:1 azobenzene- 3'- carboxylic acid-5-sulfonic acid for producing the asymmetrical urea derivative, there is obtained a dyestufi Example having the same good properties, and which yields in 11.64 parts of the aminoazo-dyestufi (prepared as direct dyeing or when after-coppered somewhat more described in the first paragraph of Example 1 by coupling reddish tints.

Example 4 Into a dyebath which contains, in 4000 parts of water, 2 parts of anhydrous sodium carbonate and 0.6 part of the dyestutf obtainable as described in Example 3 are entered at 50 C., 100 parts of cotton, and the temperature is slowly raised to the boil. 30 parts of crystalline sodium sulfate are then added and dyeing is carried on for hour at about 95 C. The greenish yellow dyeing x N ma ma arc; O l

25 in which at least one of the :substituents X represents a so obtained is distinguished by good fastness to washing and light, especially by a very good capacity for being discharged under neutral and alkaline conditions.

A somewhat more reddish yellow dyeing of better fastness to washing and light is obtained by dyeing in the manner described above and subsequently ooppering the dyeing in the same bath as follows:

HOIS

The bath is allowed to cool to 70 C., 1 part of complex sodium copper tartrate is added, the treatment is carried on for 16 hour at about 80 C., and then the cotton is rinsed with cold water.

5 What is claimed is: 1. A disazo-dyestufi which contains a single sulfonic acid group and corresponds to the formula in which R1 represents a benzene radical in which the groups N=N and -NH are in para-position relatively to one another.

2. A disazo-dyestufi which contains a single sulfonic acid group and corresponds to the formula OOOH member selected from the group consisting of a methyl and a methoxy group and a remaining X represents a hydrogen atom.

3. The disazo-dyestufi which corresponds to the for- 30 mula COOH 4. The disazo-dyestufi which corresponds to the formula OOOH 5. The disazo-dyestufi which corresponds to the formula OH: OOOH N'H-E-NH N=N OH H;

References Cited in the file of this patent UNITED STATES PATENTS 1,782,682 Geller Nov. 25, 1930 1,843,670 Gunther et a1. Feb. 2, 1932 2,375,561 Kaiser May 8, 1945 2,667,477 Liechti Ian. 26, 1954 FOREIGN PATENTS 263,524 Switzerland Aug. 31, 1949 

1. A DISAZO-DYESTUFF WHICH CONTAINS A SINGLE SULFONIC ACID GROUP CORRESPONDS TO THE FORMULA 